They coordinate with the rangers - unlike other maps - and update portages.  On a trip 3-3 years ago up through Isabella and Kahs, across Trant, and down S-Chain my 10 year old Chrismar had 4 portages (5 if you count the meadows between Side and Kahs) in the wrong place. They'd all been moved and were shown correctly on the then current Chrismar at the rangers station.

MacKenzie and Fishers were also wrong plus more.